Application of the regular mode method to the experimental determination of thermal conductivity of fluid

The article discusses widely used methods for determining the thermal conductivity of a nanofluid: the heated filament (wire) method and the $3\omega$-wire method. It is proposed to use the regular mode method to determine the thermal conductivity. The design features of the measuring calorimeter and the experimental methodology are demonstrated: the duration of the experiment should be at least $800$ s with a coefficient of heat transfer from the thermostatic fluid to the calorimeter surface of at least $2000$ W/(m$^2$ K). Studies conducted on distilled water showed a deviation from the tabulated data by $10$–$11\%$. Further studies using calorimeters of other designs seem promising.